A dazzling gold-flecked 1907 portrait by Gustav Klimt has been purchased for the Neue Galerie in Manhattan by the cosmetics magnate Ronald S. Lauder for $135 million, the highest sum ever paid for a painting.

The portrait, of Adele Bloch-Bauer, the wife of a Jewish sugar industrialist and the hostess of a prominent Vienna salon, is considered one of the artist's masterpieces. For years, it was the focus of a restitution battle between the Austrian government and a niece of Mrs. Bloch-Bauer who argued that it was seized along with four other Klimt paintings by the Nazis during World War II. In January all five paintings were awarded to the niece, Maria Altmann, now 90, who lives in Los Angeles, and other family members.

Although confidentiality agreements surrounding the sale forbid Mr. Lauder to disclose the price, experts familiar with the negotiations, speaking on condition of anonymity, said he paid $135 million for the work. In a telephone interview Mr. Lauder did not deny that he had paid a record amount for the painting, eclipsing the $104.1 million paid for Picasso's 1905 "Boy With a Pipe (The Young Apprentice)" in an auction at Sotheby's in 2004.

"This is our Mona Lisa," said Mr. Lauder, a founder of the five-year-old Neue Galerie, a tiny museum at Fifth Avenue and 86th Street devoted entirely to German and Austrian fine and decorative arts. "It is a once-in-a-lifetime acquisition." He said Christie's had helped him negotiate the purchase.

For most of the last 60 years the portrait has hung in the Austrian Gallery in the Belvedere Palace in Vienna near "The Kiss," another gold-flecked Klimt masterpiece of the Art Nouveau era. With its sinuous lines and intricate details, the painting, "Adele Bloch-Bauer I," was commissioned by the subject's husband, Ferdinand Bloch-Bauer. Mrs. Bloch-Bauer died of meningitis in 1925 at 43. In her will she requested that the painting and four others by Klimt that the couple owned be left to Austria upon her husband's death. But when Germany annexed Austria in March 1938, Mr. Bloch-Bauer fled, leaving all of his possessions behind. The Nazi government confiscated his property, placed three of the paintings in the Austrian Gallery and sold the rest.

Before Mr. Bloch-Bauer died, in November 1945, having spent the war years in Switzerland, he revoked all previous wills and drafted a new one. Since he and Adele had no children, he left his entire estate to three children of his brother Gustav: Robert, Luise and Maria.

Of the three, only Maria Altmann is still living: she and her husband, Fritz, fled Austria during the war and settled in Los Angeles in 1942. She has a niece and two nephews; a cousin of her brother's second wife also survives.

In a telephone interview on Friday Mrs. Altmann said she had met Mr. Lauder, a former American ambassador to Austria, some years ago and that she had visited the Neue Galerie when it first opened in November 2001.

"Mr. Lauder has a great understanding of Austria and a great love for Klimt," she said, adding that neither she nor her relatives felt it was practical for any of them to keep the painting, which depicts her aunt, whom she remembers from her childhood but who died when she was just 9.

That Mrs. Altmann and her relatives have possession of the painting is a tale of perseverance and tenacity. After the war the family tried to regain their stolen possessions, including the paintings, porcelains, palaces and the sugar company founded by Mr. Bloch-Bauer. Much of the artwork was divided up among the top Nazis, including Hitler and Hermann Göring; Reinhardt Hedrick, a Nazi commander, occupied a summer palace owned by Mr. Bloch-Bauer outside Prague.

The heirs were able to recover some of the works, but the Austrian authorities ruled that Mrs. Bloch-Bauer's will had essentially bequeathed the Klimts to Austria. Without access to the original documents, the family had no case.

By the mid-1980's journalists had begun investigating the restitution claim, and in 1998 Hubertus Czernin, a Viennese journalist researching the case for The Boston Globe, was able to find the documents, including Mrs. Bloch-Bauer's will, which expressed a wish — but did not require — that the Klimts go to Austria.

In 2000 Mrs. Altmann and the other heirs sued the Austrian government in the United States. Austria went to court to seek a dismissal of the suit, and the case wended its way to the United States Supreme Court, which in June 2004 ruled that Mrs. Altmann could sue Austria in the United States.

In January an arbitration tribunal in Austria decided in favor of Mrs. Altmann and her fellow heirs, awarding them the five paintings. In addition to "Adele Bloch-Bauer I" they include a second portrait of Adele, from 1911, and three landscapes: "Beechwood" (1903), "Apple Tree I" (circa 1911) and "Houses in Unterach on Lake Atter" (1916). After the settlement, Steven Thomas, the lawyer representing the Bloch-Baur heirs, said he had been approached by museums and collectors around the world who were interested in buying one or more of the paintings.

Mrs. Altmann said he had felt especially receptive to Mr. Lauder because throughout all the years the family was struggling to reclaim the art, he consistently kept in touch with her, offering to help in any way he could. "He was incredibly generous and constantly supportive," she said.

In April Mrs. Altmann and her heirs lent the paintings to the Los Angeles County Museum of Art, where they remain on view through June 30. Then the five works will travel to the Neue Galerie, where "Gustav Klimt: Five Paintings From the Collection of Ferdinand and Adele Bloch-Bauer" will be on view from July 13 through Sept. 18.

Mrs. Altmann said that when the gold portrait of her aunt finally hangs in the Neue Galerie, she will feel that it is finally where it belongs. The painting, which took Klimt three years to create, shows her aunt regally posed, with a mysterious gaze, sensuous red lips and her hands twisted near her face to conceal a deformed finger. He used gold throughout the richly painted background and in the glistening fabric of Adele's patterned gown. Art historians and chroniclers of Vienna society in the early 20th century have suggested that the artist and Ms. Bloch-Bauer were lovers.

"I never saw her smile," Mrs. Altmann recalled in Friday in the interview. "She was always very serious and wore flowing white dresses and carried a gold cigarette holder when it was very unusual for women to smoke. She would have loved to have been a woman of today, to go to university and to get involved in government."

Mrs. Bloch-Bauer was known for giving frequent parties and surrounding herself with many of the great artists, politicians and intellectuals of the day, among them the composer Richard Strauss. "She didn't have teas for ladies like my mother," Ms. Altmann said. That wasn't down her alley."

She said although Adele was very close to Mrs. Altmann's mother, Therese, she also seemed to resent her at times because Therese had a house full of healthy children and Adele had endured three tragic births. (One child died three days after it was born, and two others died within hours.)

She remembers asking her mother about the rumored love affair between Klimt and her aunt. "My mother got mad and said, 'How dare you ask such a thing? It was an intellectual friendship,' " she recalled. "But I think it was very possible there was a romance."

Of Klimt, who died in 1918, when Ms. Altmann was just a toddler, she remembers hearing that he often wore a floor-length smock with nothing underneath.

After Adele died, seven years after Klimt, her husband created a kind of shrine to her in what had been their bedroom. "The Klimts were always in the bedroom, but after she died, the bed was removed and there were always fresh flowers," Mrs. Altmann said.

As for the other four paintings, experts estimate that they are together worth some $100 million.

The fate of these four has yet to be determined. "I can't decide," Mrs. Altmann said. "Maybe after they leave the Neue Galerie, they will go to Christie's. I very much hope they end up in museums. But for now I am just happy they have a home at the Neue Galerie. It is very deserved. I couldn't have wished for a better place."